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 MSA  Vol.8 No.2 , February 2017
The Effect of Tin on PECVD-Deposited Germanium Sulfide Thin Films for Resistive RAM Devices
Abstract: Resistive RAM is a promising, relatively new type of memory with fast switching characteristics. Metal chalcogenide films have been used as the amorphous semiconductor layer in these types of devices. The amount of crystallinity present in the films may be important for both reliable operation and increased longevity of the devices. Germanium sulfide films can be used for these devices, and a possible way to tune the crystalline content of the films is by substituting Sn for some of the Ge atoms in the film. Thin films of GexSnySz containing varying amounts of tin were deposited in a plasma enhanced chemical vapor deposition reactor. Films with 2%, 8%, 15%, 26%, and 34% atomic percentage Sn were deposited to determine crystallinity and structural information with XRD and Raman spectroscopy. Based on these depositions it was determined that at about 8% Sn content and below, the films were largely amorphous, and at about 26% Sn and above, they appeared to be largely crystalline. At 15% Sn composition, which is between 8% and 26%, the film is more a mixture of the two phases. Based on this information, current-voltage (IV) curves of simple memory switching devices were constructed at 5% Sn (in the amorphous region), at 25% Sn (in the crystalline region), and at 15% (in the mixed region). Based on the IV curves from these devices, the 15% composition gave the best overall switching behavior suggesting that a certain degree of order in the semiconductor layer is important for RRAM devices.
Cite this paper: Rodriguez, R. , Poulter, B. , Gonzalez, M. , Ali, F. , Lau, L. and Mangun, M. (2017) The Effect of Tin on PECVD-Deposited Germanium Sulfide Thin Films for Resistive RAM Devices. Materials Sciences and Applications, 8, 188-196. doi: 10.4236/msa.2017.82012.
References

[1]   Edwards, A., Barnaby, H., Campbell, K., Kozicki, M. and Liu, W. (2015) Reconfigurable Memristive Device Technologies. Proceedings of the IEEE, 103, 1004-1032.
https://doi.org/10.1109/JPROC.2015.2441752

[2]   Wang, F., Dunn, W., Jain, M., Leo, C. and Vickers, N. (2011) The Effects of Active Layer Thickness on Programmable Metallization Cells Based on Ag-Ge-S. Solid State Electronics, 61, 33-37.
https://doi.org/10.1016/j.sse.2011.01.042

[3]   Jameson, J., Gilbert, N., Koushan, F., Saenz, J., Wang, J., Hollmer, S., Kozicki, M. and Derhacobian, N. (2012) Quantized Conductance in Ag/GeS2/W Conductive-Bridge Memory Cells. IEEE Electron-Device Letters, 33, 257-259.
https://doi.org/10.1109/LED.2011.2177803

[4]   Campbell, K. and Anderson, C. (2006) Phase Change Memory Devices with Stacked Ge-Chalcogenide/Sn-Chalcogenide Layers. Microelectronics Journal, 38, 52-59.
https://doi.org/10.1016/j.mejo.2006.09.012

[5]   Vianello, E., Molas, G., Longnos, F., Blaise, P., Souchier, E., Cagli, C., Palma, G., Guy, J., Bernard, M., Reyboz, M., Rodriguez, G., Roule, A., Carabasse, C., Delaye, V., Jousseaume, V., Maitrejean, S., Reimbold, G., DeSalvo, B., Dahmani, F., Verrier, P., Bretegnier, D. and Liebault, J. (2012) Performance and Reliability Booster in Conductive Bridge RAM. Proceedings of the 2012 International Electron Devices Meeting, San Francisco, 741-744.
https://doi.org/10.1109/IEDM.2012.6479145

[6]   Whitham, P., Strommen, D., Lundell, S., Lau, L. and Rodriguez, R. (2014) GeS2 and GeSe2 PECVD from GeCl4 and Various Chalcogenide Precursors. Plasma Chemistry and Plasma Processing, 34, 755-766.
https://doi.org/10.1007/s11090-014-9542-4

[7]   Whitham, P., Strommen, D., Lau, L. and Rodriguez, R. (2011) Thin Film Growth of Germanium Selenides from PECVD of GeCl4 and Dimethyl Selenide. Plasma Chemistry and Plasma Processing, 31, 251-256.
https://doi.org/10.1007/s11090-010-9278-8

[8]   Price, L., Parkin, I., Hardy, A., Clark, R., Hibbert, T. and Molloy, K. (1999) Atmospheric Pressure Chemical Vapor Deposition of Tin Sulfides (SnS, Sn2Sn3, and SnS2) on Glass. Chemistry of Materials, 11, 1792-1799.
https://doi.org/10.1021/cm990005z

[9]   Phillips, B., Steidley, S., Lau, L. and Rodriguez, R. (2001) Coherent Raman Spectroscopic Monitoring of Pulsed Radio Frequency PECVD of Silicon Nitride Thin Films. Journal of Applied Spectroscopy, 55, 946-951.
https://doi.org/10.1366/0003702011952785

[10]   Shimada, M. and Dachille, F. (1977) Crystallization of Amorphous Germanium Sulfide and Germanium Selenide under Pressure. Inorganic Chemistry, 16, 2094-2097.
https://doi.org/10.1021/ic50174a055

[11]   Lin, Y., Shi, J., Chen, Y., Chen, C. and Wu, P. (2009) Synthesis and Characterization of Tin Disulfide (SnS2) Nanowires. Nanoscale Research Letters, 4, 694-698.
https://doi.org/10.1007/s11671-009-9299-5

[12]   Sakaguchi, Y., Tenne, D. and Mitkova, M. (2009) Oxygen-Assisted Photoinduced Structural Transformation in Amorphous Ge-S Films. Physica Status Solidi B, 246, 1813-1819.
https://doi.org/10.1002/pssb.200982009

[13]   Mitkova, M., Chen, P., Ailavajhala, M., Butt, D., Tenne, D., Barnaby, H. and Esqueda, I. (2013) Gamma Ray Induced Structural Effects in Bare and Ag Doped Ge-S Thin Films for Sensor Application. Journal of Non-Crystalline Solids, 377, 195-199.
https://doi.org/10.1016/j.jnoncrysol.2012.12.031

[14]   Smith, A., Meek, P. and Liang, W. (1977) Raman Scattering Studies of SnS2 and SnSe2. Journal of Physics C: Solid State Physics, 10 1321-1333.
https://doi.org/10.1088/0022-3719/10/8/035

 
 
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